CN105169969A - Preparation method of high-performance composite membrane used for water treatment - Google Patents

Abstract

The invention relates to a preparation method of a high-performance composite membrane used for water treatment. According to the preparation method, interfacial polymerization is adopted so as to prepare a functional layer on a porous support membrane. In preparation processes, an adopted water-phase reaction solution contains an in-suit generated inorganic nano hydroxide with excellent dispersity; interaction of the nano-scale hydroxide with groups in the functional layer enables that the nano-scale hydroxide can be coated by the network structure of the functional layer firmly, and the high-performance composite membrane is provided with long-term stable hydrophilic performance, chlorine resistance, pollution resistance, antibacterial properties, and excellent separation performance.

Description

Preparation method of high-performance composite membrane for water treatment

technical field

The invention belongs to the technical field of polymer membranes, and in particular relates to a preparation method of a high-performance composite membrane for water treatment.

Background technique

At present, most of the composite membranes for water treatment are composite nanofiltration or reverse osmosis membranes obtained by polymerizing polyamines and polyacyl chlorides on the surface of porous support membranes. The cross-linked aromatic polyamides in the functional layer of the resulting composite membranes are extremely vulnerable to active chlorine attack. As a result, the performance of the membrane is reduced or even exhausted, and the service life of the membrane is shortened, which greatly limits the application of nanofiltration/reverse osmosis composite membranes in water treatment. In addition, the hydrophilicity and stain resistance of the surface of the conventional cross-linked aromatic polyamide functional layer need to be further improved. When the composite membrane is used in water treatment, the fungi in various water qualities will lead to a sharp drop in the flux of the composite membrane, which requires frequent chemical cleaning, resulting in an increase in water costs and a decrease in the service life of the membrane. Therefore, it is of great significance to develop high-performance composite membranes with excellent hydrophilicity, chlorine resistance, pollution resistance, antibacterial properties and separation performance. Among them, the excellent performance of the functional layer determines the performance of the final composite membrane.

At present, the modification of the functional layer is mainly achieved through the following two methods: 1. Developing a high-performance aqueous or organic phase reaction monomer to obtain a modified functional layer; 2. Directly modifying the existing functional layer materials. Among them, the second method is simple and effective, and it is also a hotspot of modification at present. Direct modification of existing functional layer materials can be divided into two categories: functional layer surface modification and bulk modification. Surface modification is by introducing modifying groups on the surface of the functional layer, mainly including surface grafting and surface coating. The bulk modification is to change the material composition of the functional layer, mainly by blending. Among them, the blending method is simple and can more effectively achieve the purpose of overall modification of the functional layer.

Chinese patent document CN104587845 introduces a composite membrane with a hydrophilic separation layer. The separation layer is prepared on the porous support membrane by interfacial polymerization. amine, the prepared separation layer has long-term stable hydrophilicity, and can be used in processes such as nanofiltration, reverse osmosis, pervaporation, and forward osmosis, but the nanofiltration membrane prepared by this method does not consider the presence of ether oxygen groups in the separation layer. Introduce effects on membrane chlorine resistance, antibacterial properties, etc. Chinese patent document CN104379243 has developed a polyamide water treatment separation membrane with excellent oxidation resistance and chlorine resistance and its preparation method. The polyamide layer in the membrane contains a solubility parameter value of 9-22 (J/cm ³ ) ^1/2 of the phenolic antioxidants, but this method does not consider the effect of the addition of phenolic antioxidants on membrane separation performance, including flux and rejection.

Contents of the invention

In view of the above problems, the present invention provides a method for preparing a high-performance composite membrane for water treatment, by in situ introducing into the polyamide functional layer an inorganic hydroxide that has surface hydrophilicity and can interact with negatively charged carbonyl groups in polyamide molecules The resulting composite membrane has long-term stable hydrophilicity, chlorine resistance, anti-pollution, antibacterial and excellent separation performance.

In order to solve the above problems, the present invention is realized through the following technical solutions:

A method for preparing a high-performance composite membrane for water treatment is designed. The functional layer of the composite membrane is composited on a porous support membrane by interfacial polymerization.

Specifically include the following steps:

(1) Preparation of aqueous phase reaction solution:

Add sodium hydroxide aqueous solution dropwise to the inorganic chloride aqueous solution with a concentration of 0.01 to 18wt%, until the pH of the solution reaches neutrality, and then add polyamine monomers to the solution to make the concentration of the polyamine monomers 1~6wt%, and then stirred at 20~50°C for 10~60min; the obtained aqueous phase reaction solution contains in-situ generated inorganic nano-hydroxide, which can interact with groups in the functional layer Force, so that it is firmly wrapped in the network structure of the functional layer on the surface of the composite membrane;

(2) Preparation of organic phase reaction solution:

Add polybasic acid chloride monomers to at least one solvent of n-hexane and n-heptane, so that the concentration of the polybasic acid chloride monomers is 0.1-4wt%, and after they are completely dissolved at room temperature, put them into a closed container and fill Inert gas (such as nitrogen, etc.) preservation;

(3) Composite film coating process:

Completely immerse the porous support membrane in the aqueous phase reaction solution, take it out after 2-30 minutes, remove the water droplets on the surface of the porous support membrane, put it in a constant temperature drying oven at 30-60°C for 2-720 minutes, take it out, and then completely immerse it in the organic phase reaction solution Take it out for 5-600 seconds, place it in a constant temperature drying oven at 30-70°C for 5-720 minutes, take it out, and soak it in pure water for 20-30 hours to obtain a high-performance composite membrane for water treatment.

Preferably, the polyamine monomer is at least one of m-phenylenediamine, piperazine, o-phenylenediamine, p-phenylenediamine, and polydopamine.

Preferably, the inorganic chloride is at least one of copper chloride, ferric chloride, ferrous chloride, zinc chloride, aluminum chloride, and magnesium chloride.

Preferably, the polybasic acid chloride monomer is at least one of biphthaloyl chloride, biphenyltetrayl chloride, biphenylhexayl chloride, trimesoyl chloride, isophthaloyl dichloride, and isophthaloyl dichloride.

Preferably, the porous support membrane is a flat plate, tubular or hollow fiber type, and the material of the porous support membrane is polysulfone, polyethersulfone, polyvinylidene fluoride, sulfonated polysulfone, sulfonated polyethersulfone, poly At least one of tetrafluoroethylene and polypropylene.

Preferably, filter paper, sponge, air knife or nitrogen flow are used in step (3) to remove water droplets on the surface of the porous support membrane.

Positive beneficial effect of the present invention:

The composite membrane obtained in the invention can be used in the preparation of nanofiltration and reverse osmosis composite membranes. The aqueous phase reaction solution used in the preparation process of the present invention contains inorganic nano-hydroxides generated in situ, and the well-dispersed nano-scale hydroxides and their interaction with groups in the functional layer enable them to be firmly wrapped in the functional layer. In the network structure of the layer, the obtained composite membrane has long-term stable hydrophilicity, chlorine resistance, pollution resistance, antibacterial property and excellent separation performance.

Detailed ways

The technical solution of the present invention will be further described below in conjunction with specific embodiments.

Example 1

A method for preparing a high-performance composite membrane for water treatment, the steps are as follows:

(1) Preparation of aqueous phase reaction solution: prepare a copper chloride aqueous solution with a concentration of 0.5wt%, and obtain a clear and translucent solution after the dissolution is complete. Add an equal stoichiometric sodium hydroxide aqueous solution to the solution drop by drop until the pH of the solution reaches 7 up to; add m-phenylenediamine in this solution, make its concentration be 3wt%, then stir 30min at 30 ℃;

(2) Prepare the organic phase reaction solution: add trimesoyl chloride to n-hexane solvent to make the concentration of trimesoyl chloride 0.1wt%, and after the solution is completely dissolved at room temperature, put it into a closed container and fill it with nitrogen to store it for later use;

(3) Composite membrane coating: The porous support membrane is a polysulfone flat membrane scraped on the non-woven fabric; the porous support membrane is completely immersed in the aqueous phase reaction solution for 2 minutes, then taken out, and the excess water droplets on the membrane surface are removed, then put into Bake in a constant temperature drying oven at 30°C for 600 minutes, take it out, completely immerse it in the organic phase reaction solution for 5 seconds, take it out and put it in a constant temperature drying oven at 30°C for 720 minutes, take it out, soak it in pure water for 24 hours, and you will get a flat plate composite reverse osmosis membrane.

Comparative example 1

Preparation of aqueous phase reaction liquid: add 3wt% m-phenylenediamine to pure water, stir at 30°C for 30min. The preparation of the organic phase reaction solution and the coating process of the composite membrane are the same as in Example 1 to obtain a flat composite reverse osmosis membrane.

Example 2

A method for preparing a high-performance composite membrane for water treatment, the steps are as follows:

(1) Preparation of aqueous phase reaction solution: prepare a zinc chloride aqueous solution with a concentration of 0.5wt%, and obtain a clear and translucent solution after complete dissolution, and add an equal stoichiometric sodium hydroxide aqueous solution drop by drop to the solution system pH Up to 7, add piperazine to the solution to make the concentration 3wt%, and stir at 20°C for 60min;

(2) Prepare the organic phase reaction solution: add biphenyltetrayl chloride to the n-heptane solvent to make the concentration 3wt%, and after it is completely dissolved at room temperature, put it into a closed container and store it with nitrogen gas;

(3) Composite membrane coating: The porous support membrane is a dry-wet spinning polysulfone hollow fiber membrane. Completely immerse the porous support membrane in the aqueous phase reaction solution for 10 minutes, take it out, remove excess water droplets on the surface of the membrane, put it in a constant temperature drying oven at 60°C for 60 minutes, take it out, and completely immerse it in the organic phase reaction solution for 60 seconds, take it out and put it Dry it in a constant temperature drying oven at 60°C for 10 minutes, take it out, and soak it in pure water for 24 hours to obtain a hollow fiber composite nanofiltration membrane.

Comparative example 2

Preparation of aqueous phase reaction solution: add 3wt% piperazine to pure water, stir at 20°C for 60min, and stop. The preparation of the organic phase reaction liquid and the coating process of the composite membrane are the same as in Example 2, and the hollow fiber composite nanofiltration membrane is obtained.

Example 3

A method for preparing a high-performance composite membrane for water treatment, the steps are as follows:

(1) Prepare the aqueous phase reaction solution: prepare a mixed aqueous solution of magnesium chloride and copper chloride with a concentration of 4wt% (mass ratio = 25%: 75%), and obtain a clear and translucent solution after the dissolution is complete. Add the solution drop by drop, etc. Stoichiometric sodium hydroxide aqueous solution, until the pH of the solution system reaches 7, add o-phenylenediamine to the solution to make the concentration 4wt%, and stir at 40°C for 45min;

(2) Prepare the organic phase reaction solution: add isophthaloyl chloride to the mixed solvent of n-heptane and n-hexane (volume ratio = 10%:90%) to make the concentration 0.6wt%, and dissolve it completely at room temperature , into an airtight container, filled with nitrogen for storage.

(3) Composite membrane coating: The porous support membrane is a blended flat membrane of sulfonated polyethersulfone/polyethersulfone (mass ratio = 20%: 80%). Completely immerse the porous support membrane in the aqueous phase reaction solution for 90 minutes, take it out, remove excess water droplets on the surface of the membrane, put it in a constant temperature drying oven at 30°C for 240 minutes, take it out, and completely immerse it in the organic phase reaction solution for 240 seconds, then take it out Put it into a constant temperature drying oven at 30°C for 720 minutes, take it out, and soak it in pure water for 24 hours to obtain a flat composite reverse osmosis membrane.

Comparative example 3

Preparation of aqueous phase reaction solution: add 4wt% o-phenylenediamine to pure water, stir at 40°C for 45 minutes, and stop. The preparation of the organic phase reaction solution and the coating process of the composite membrane were the same as in Example 3, and a flat composite reverse osmosis membrane was obtained.

Example 4

A method for preparing a high-performance composite membrane for water treatment, the steps are as follows:

(1) Preparation of aqueous phase reaction solution: prepare an aqueous solution of aluminum chloride with a concentration of 0.6wt%, and obtain a clear and translucent solution after dissolution is complete, and add an equal stoichiometric sodium hydroxide aqueous solution drop by drop to the solution system pH Up to 7, add p-phenylenediamine to the solution to make the concentration 3wt%, and stir at 50°C for 10 minutes;

(2) Prepare the organic phase reaction solution: add trimesoyl chloride to the n-heptane solvent to make the concentration 2wt%, and after it is completely dissolved at room temperature, put it into a closed container and store it with nitrogen gas;

(3) Composite membrane coating: the porous support membrane is a polypropylene tubular membrane. Completely immerse the porous support membrane in the aqueous phase reaction solution for 120 minutes, take it out, remove excess water droplets on the surface of the membrane, put it in a constant temperature drying oven at 50°C for 60 minutes, and then take it out. Bake in a constant temperature drying oven at 70°C for 20 minutes, take it out, and soak it in pure water for 24 hours to obtain a tubular composite reverse osmosis membrane.

Comparative example 4

Preparation of aqueous phase reaction solution: add 3wt% p-phenylenediamine to pure water, stir at 50°C for 10 minutes, and stop. The preparation of the organic phase reaction solution and the coating process of the composite membrane are the same as in Example 4 to obtain a tubular composite reverse osmosis membrane.

Example 5

A method for preparing a high-performance composite membrane for water treatment, the steps are as follows:

(1) Preparation of aqueous phase reaction solution: prepare an aqueous solution of ferric chloride with a concentration of 8wt%, and obtain a clear and translucent solution after dissolution is complete, and add an aqueous sodium hydroxide solution of equal stoichiometric amount to the solution drop by drop until the pH of the solution system reaches 7, add a mixture of piperazine and polydopamine (mass ratio = 80%: 20%) to the solution, so that the concentration of the mixture is 1 wt%, and stir at 20°C for 120 minutes before stopping;

(2) Prepare the organic phase reaction solution: add biphenyltrichloride to the n-heptane solvent to make the concentration 0.8wt%, and after it is completely dissolved at room temperature, put it into a closed container and store it with nitrogen gas;

(3) Composite membrane coating: The porous support membrane is polyvinylidene fluoride hollow fiber membrane. Completely immerse the porous support membrane in the aqueous phase reaction solution for 8 minutes, take it out, remove excess water droplets on the surface of the membrane, put it in a constant temperature drying oven at 60°C for 120 minutes, take it out, and completely immerse it in the organic phase reaction solution for 600 seconds, then take it out Put it into a constant temperature drying oven and dry it at 40°C for 660 minutes, take it out, and soak it in pure water for 24 hours to obtain a hollow fiber composite nanofiltration membrane.

Comparative Example 5

Preparation of aqueous phase reaction liquid: add 1wt% piperazine and polydopamine mixture (mass ratio = 80%:20%) to pure water, stir at 20°C for 120min and stop. The preparation of the organic phase reaction solution and the coating process of the composite membrane are the same as in Example 5, and a hollow fiber composite nanofiltration membrane is obtained.

Example 6

A method for preparing a high-performance composite membrane for water treatment, the steps are as follows:

(1) Preparation of aqueous phase reaction solution: prepare a zinc chloride aqueous solution with a concentration of 2wt%, and obtain a clear and translucent solution after dissolving completely, and add an equal stoichiometric sodium hydroxide aqueous solution drop by drop to the solution until the pH of the solution system reaches 7, add a mixture of o-phenylenediamine and piperazine (mass ratio = 40%: 60%) to the solution to make the concentration of the mixture 4wt%, and stir at 50°C for 10 minutes before stopping;

(2) Prepare the organic phase reaction solution: add isophthaloyl chloride to the n-heptane solvent to make the concentration 3wt%, and after it is completely dissolved at room temperature, put it into a closed container and store it with nitrogen gas;

(3) Composite membrane coating: The porous support membrane is a melt-spun polytetrafluoroethylene hollow fiber membrane. Completely immerse the porous support membrane in the aqueous phase reaction solution for 8 minutes, take it out, remove excess water droplets on the surface of the membrane, put it in a constant temperature drying oven at 30°C for 180 minutes, take it out, and completely immerse it in the organic phase reaction solution for 20 seconds, take it out and put Dry it in a constant temperature drying oven at 30°C for 120 minutes, take it out, and soak it in pure water for 24 hours to obtain a hollow fiber composite nanofiltration membrane.

Comparative Example 6

Preparation of aqueous phase reaction solution: Add 4wt% o-phenylenediamine and piperazine mixture (mass ratio = 40%:60%) to pure water, stir at 50°C for 10 minutes, and stop. The preparation of the organic phase reaction solution and the coating process of the composite membrane are the same as in Example 6 to obtain a hollow fiber composite nanofiltration membrane.

Example 7

A method for preparing a high-performance composite membrane for water treatment, the steps are as follows:

(1) Preparation of aqueous phase reaction solution: prepare a mixed aqueous solution of zinc chloride and aluminum chloride with a concentration of 8wt% (mass ratio = 45%: 55%), and obtain a clear and translucent solution after complete dissolution, drop by drop into the solution Add a stoichiometric sodium hydroxide aqueous solution until the pH of the system reaches 7, add a mixture of m-phenylenediamine and p-phenylenediamine (mass ratio = 77%: 23%) to the solution, so that the concentration of the mixture is 5wt% , after stirring for 50 minutes at 30°C;

(2) Preparation of the organic phase reaction solution: Add a mixture of trimesoyl chloride and biphenylhexayl chloride (mass ratio = 86%: 14%) in n-hexane solvent to make the concentration 0.8wt%, and dissolve completely at room temperature , into a closed container, filled with nitrogen for storage;

(3) Composite membrane coating: the porous support membrane is a sulfonated polysulfone flat membrane. Completely immerse the porous support membrane in the aqueous reaction solution for 90 minutes, take it out, remove excess water droplets on the surface of the membrane, put it in a constant temperature drying oven at 40°C for 120 minutes, take it out, and completely immerse it in the organic reaction solution for 60 seconds, take it out and put it Dry in a constant temperature drying oven at 60°C for 10 minutes, take it out, and soak it in pure water for 24 hours to obtain a flat composite reverse osmosis membrane.

Comparative Example 7

Preparation of aqueous phase reaction solution: add 5wt% of a mixture of m-phenylenediamine and p-phenylenediamine (mass ratio = 77%: 23%) to pure water, and stir at 30°C for 50 minutes before stopping. The preparation of the organic phase reaction solution and the coating process of the composite membrane are the same as in Example 7 to obtain a flat composite reverse osmosis membrane.

Example 8

A method for preparing a high-performance composite membrane for water treatment, the steps are as follows:

(1) Preparation of aqueous phase reaction solution: prepare a copper chloride aqueous solution with a concentration of 1wt%, and obtain a clear and translucent solution after dissolving completely, and add an equal stoichiometric sodium hydroxide aqueous solution drop by drop to the solution until the pH of the solution system reaches 7, add a mixture of m-phenylenediamine and piperazine (mass ratio = 21%: 79%) to the solution to make the concentration of the mixture 2.8wt%, and stir at 40°C for 30 minutes before stopping;

(2) Prepare the organic phase reaction solution: add a mixture of trimesoyl chloride and isophthaloyl chloride (mass ratio = 65%: 35%) in n-hexane solvent, so that the concentration of the mixture is 1.2wt%, and it is completely dissolved at room temperature Finally, put it into an airtight container and fill it with nitrogen for storage;

(3) Composite membrane coating: The porous support membrane is a carboxylated polypropylene tubular membrane. Completely immerse the porous support membrane in the aqueous phase reaction solution for 30 minutes, take it out, remove excess water droplets on the surface of the membrane, put it in a constant temperature drying oven at 30°C for 150 minutes, take it out, and completely immerse it in the organic phase reaction solution for 90 seconds, then take it out Put it in a constant temperature drying oven at 50°C for 30 minutes, take it out, and soak it in pure water for 24 hours to obtain a tubular composite nanofiltration membrane.

Comparative Example 8

Preparation of aqueous phase reaction solution: add 2.8wt% of a mixture of m-phenylenediamine and piperazine (mass ratio = 21%:79%) to pure water, and stir at 40°C for 30 minutes. The preparation of the organic phase reaction solution and the coating process of the composite membrane are the same as in Example 8 to obtain a tubular composite nanofiltration membrane.

The hydrophilicity, separation performance, chlorine resistance, anti-pollution and antibacterial test results of the composite membrane prepared in each of the above embodiments and comparative examples are listed in Table 1, and the specific test methods are as follows:

Hydrophilicity test:

Characterized by the static contact angle, the larger the contact angle value, the weaker the hydrophilicity. The contact angle is measured by a three-point measurement method, and each sample is measured at five different positions, and the final average value is taken.

Separation performance test:

Including water flux J and interception rate R , calculated according to the following formulas (1) and (2):

(1)

Where V is the volume of permeated water (L), S is the membrane area (m ² ), t is the test time (h), and the test pressure is 0.1MPa;

(2)

In the formula, R is the rejection rate (%); C ₀ and C _p are the conductivity values of the stock solution and the permeate, respectively.

Chlorine resistance test:

Prepare 100ppm, pH6.5 NaClO aqueous solution, place it in a dark environment, soak the prepared composite membrane in the above solution for 24 hours, take out pure water and rinse, test the separation performance of the composite membrane, until the separation performance deteriorates sharply, record the soaking number of days.

Pollution resistance test:

Preparation of bovine serum albumin phosphate buffer solution (BSA/PBS): weigh NaCl (137mmol, 8.00g), KCl (2.7mmol, 0.20g), Na ₂ HPO ₄ (10.0mmol, 1.44g), KH ₂ PO ₄ ( 1.76mmol, 0.24g), BSA (1.00g) was dissolved to 1L to obtain 1g ^. L ^-1 BSA/PBS solution.

The anti-fouling behavior of the membrane was characterized by a three-cycle method. Cut the membrane to a certain size and put it into the test cell. First, pure water is used as the raw material solution, and the permeate volume is recorded every 3 minutes under 0.1 MPa, and ten values are taken to calculate the corresponding pure water flux. Cycle 1: Replace the pure water with BSA/PBS buffer solution, adjust the pressure to 0.1MPa, measure the permeate volume every 3 minutes, take ten values, and calculate the corresponding water flux. Then rinse the diaphragm with pure water, and after 30 minutes, use pure water as the raw material solution. Under 0.1MPa, the flux is recorded every 3 minutes, and ten values are taken. The test process of cycle 2 and 3 is the same as that of cycle 1. The fouling resistance of the membrane was evaluated by examining the relative recovery rate ( R _FR ) of the pure water flux before and after the membrane was inserted into the BSA/PBS solution. The calculation formula is as follows:

(3)

In the formula, R _FR is the flux relative recovery rate, %; J _R is the pure water flux of the polluted membrane after cleaning, L ^. m ^-2. h ^-1 ; J ₀ is the initial pure water flux of the membrane, L ^. m ^-2. h ^-1 .

Antibacterial test:

Prepare an aqueous solution containing 1wt% tryptone, 0.5wt% yeast and 0.1wt% NaCl, and adjust the pH value to 7. Shake (180rpm) overnight at 37°C to obtain a bacterial culture solution. After immersing the composite membrane prepared by the invention in the above-mentioned bacterial culture solution for 24 hours, the separation performance of the composite membrane was tested after taking out pure water and rinsing. The fouling resistance performance of the membrane is evaluated by examining the change rate ( C %) of the pure water flux before and after the membrane is immersed in the bacterial culture solution. The calculation formula is as follows:

(4)

In the formula, C % is the flux change rate, %; J ₀ and J _t are the pure water flux before and after the composite membrane is immersed in the bacterial culture solution, L ^. m ^-2. h ^-1 .

.

.

Note: NF means nanofiltration membrane; RO means reverse osmosis membrane. In the table, the water flux and rejection of the prepared composite nanofiltration membrane and reverse osmosis membrane are tested by 1g/L MgSO ₄ and NaCl aqueous solution, test pressure: 0.7MPa, and test temperature: 25°C.

The present invention is not limited to the specific embodiments described above, and those skilled in the art can also make various changes accordingly, but any changes that are equivalent or similar to the present invention should be covered within the scope of the claims of the present invention.

Claims (7)

1. a preparation method for water treatment high performance composite membrane, is characterized in that: the functional layer of described composite membrane is by interfacial polymerization, and on porous support membrane, compound obtains.

2. the preparation method of water treatment high performance composite membrane according to claim 1, is characterized in that, comprise the following steps:

(1) preparation of aqueous phase reactions liquid:

Be drip sodium hydrate aqueous solution in the butter aqueous solution of 0.01 ~ 18wt% to concentration, to the pH of solution reaches neutrality, in solution, add polynary amine monomers again, make the concentration of described polynary amine monomers be 1 ~ 6wt%, then stir 10 ~ 60min at 20 ~ 50 DEG C; Containing the inorganic nano hydroxide that original position produces in gained aqueous phase reactions liquid, this hydroxide can produce interaction force with the group in functional layer, makes it firmly be wrapped in the network structure of composite film surface functional layer;

(2) preparation of organic phase reactant liquor:

Add polynary acyl chloride monomer at least one solvent in n-hexane and normal heptane, the concentration making described polynary acyl chloride monomer is 0.1 ~ 4wt%, dissolves completely, load in closed container under room temperature, is filled with inert gas and preserves;

(3) composite membrane coating process:

Porous support membrane is immersed into completely in aqueous phase reactions liquid, take out after 2 ~ 30min, remove porous support membrane surface water droplet, be placed in thermostatic drying chamber 30 ~ 60 DEG C and dry 2 ~ 720min taking-up, be immersed into 5 ~ 600S in organic phase reactant liquor more completely to take out, be placed in thermostatic drying chamber 30 ~ 70 DEG C and dry 5 ~ 720min taking-up, in pure water, soak 20 ~ 30h, namely obtain water treatment high performance composite membrane.

3. the preparation method of water treatment high performance composite membrane according to claim 2, is characterized in that: described polynary amine monomers is at least one in m-phenylene diamine (MPD), piperazine, o-phenylenediamine, p-phenylenediamine (PPD), poly-dopamine.

4. the preparation method of water treatment high performance composite membrane according to claim 2, is characterized in that: described butter is at least one in copper chloride, iron chloride, frerrous chloride, zinc chloride, aluminium chloride, magnesium chloride.

5. the preparation method of water treatment high performance composite membrane according to claim 2, is characterized in that: described polynary acyl chloride monomer is at least one in biphenyl three acyl chlorides, biphenyl four acyl chlorides, biphenyl six acyl chlorides, pyromellitic trimethylsilyl chloride, isophthaloyl chloride, m-phthaloyl chloride.

6. the preparation method of water treatment high performance composite membrane according to claim 2, it is characterized in that: described porous support membrane is flat board, tubular type or hollow fiber form, and the material of described porous support membrane is at least one in polysulfones, polyether sulfone, Kynoar, SPSF, sulfonated polyether sulfone, polytetrafluoroethylene (PTFE), polypropylene.

7. the preparation method of water treatment high performance composite membrane according to claim 2, is characterized in that: adopt filter paper, sponge, air knife or nitrogen diffluence except the water droplet on porous support membrane surface in step (3).